Signal-transmission system



1,628,009 9 A. H, TAYLOR SIGNAL TRANSMISSION SYSTEVMI Filed Sept. 20. 1926 .INVENTOR.

ATTORNEY arm H. marries, wasiarrre'rou,

rare, or NEW zoair, r11

rarer or coriuatara .e coaroiaarrcu time Apclicatiea silos September 20, 192%. Serial Hoe 1-23,?32;

My invention relates broadly to high voltage generator its same range of volt- :trequeucy signal transmission systems and more particularly to circuits for high power electron tuhe irarisuiitters.

Que of the objects of my invention is to provide a circuit arrangement for a high power electron tube transmitter employing Oscillator and a power amplifier tubes, wherein a high potential circuit is provided for simultaneously delivering the plate supply voltage for the oscillator tube and the grid biasing potential for the grower amplilier tube I I Another ohject oi my invention is to pro vide a circuit arrangement for an electron tube transmitter employing apiezo electric crystal control circuit for the oscillator of the electron tube system with a power amplifier or frequency multiplier connected to the output circuit of the oscillator with a circuit arrangement for supplying high voltage to the oscillator and biasing poterr tial to the povver amplifier or frequency multiplier for facilitating the use of the secend and third harmonics of the master oscillator in the power amplifier.

Still another object of my invention is to provide a circuit arrangement for a master oscillator and power amplifier oi an electron tube transmission system in which a keying circuit is interposed, between 'hllfllilfgll potential source for the oscilla or cl the grid circuit of the power amp ior the trans mission oi"- sigiials under coriiiol of a pie'zo electric crystal 'Zrequeucy c' t-rcl circuit My invention will he clearly understood from the speciiicatcreiuaiter l oliovviug loy referring to t accomoauyiu dravvirig which diagrauura; v the principles on? my invention or an electron tuhe transmission system, i coui-ectiou the operation of trausri ers ea t iigh frequency trail" fitters an ecially those provided coutrol 1t lace-o r $1.611 I .1 3 voltage, a, ,3 the same crdc plate voltse on t a, volta e ing volts .o. C. to the r later til; ans 1:

relatively high potentials Y on opposite sides of age namely 220 to 588 for the negative voltage or; the grid of the power amplifier when same is used as fret iency multiplier.

By my present .uver ioe. I employ a special circuit hetvzceu he electron tuhe oscillator and power amplifier systems in which there is interposed a source of potential for simultaneously supplying the plate voltage for the mas oscillator tube and the biasing pets :for the frequency multiplier tube or ower amplifier. A. circuit connecting-the source to the grid of the power amplifier tube :caay be utilized as the keying circuit for precise on of signals. Special provision is insulating the filament circuit of the oscillator against the olyed in the systeru.

Referring to the drawing is more detail, refrerence character 1 designates the electron tuoe which functions as an oscillator for the transmission system. The electron tube 1 contains cathode grid electrode 3 and plate electrode A element trausiormer 5 is provided for" supplying the filament electrodes of the oscillator tube or tubes 1, the filament transformer including" a primar winding 6 and a secondary winding especially insulated for withstanding the high potentials involved in this type of circult that is of a nature of 500, volts or more. Alternating current may (be supplied to the primary Winding 6 and for securing smooth operation of the electron tuhe circuit balancing condensers 9 and 19 are provided "dcorrection 8 on secondary Wind The input circuit shown at 11 as incl l device 12 hetvveeu connected iu. series 1' deieser lid to the 1* 'lectrori tube are arranger electric crystal circa rcuit of the electi to oscillato has been mere electric a mission of signals.

- electric crystal control ti circuit of the oscillator through variable in ductance 23 tuned by condenser 25 and -couplcd through condenser 24% with the plate circuit of tube 1. Amrncter A isarranged in the tuned circuit 2325 between the power amplifier and oscillator tubes. The output circuit of power amplifier or frequency multiplier tube 17 includes condenser 26 and inductance 27 tuned by vari able condenser 28. The high potential for the plate supply circuit of the frequency multiplier or power amplifier is supplied from either an alternating or direct current source. I have successfully used both alternating and direct current in the output circuit of the frequency multiplier tube.

In the drawings I have illustrated an alternating current source 32 and have represented akey 33 in circuit therewith which may interrupt the plate supply circuit for the production of signals. The cathode circuit for the frequency multiplier tube has been shown as connected to a ground or counterpoise at 36. A suitable choke 34c is connected in the high potential supply c1rcuit in series with the plate electrode 20 of the electron tube 1 7. The output circuit of the power amplifier or frequency multiplier is coupled to the inductance 29 in the antenna ground circuit 30-31..

The circuit of my invention is illustrated between the plate elecrode 4 of the oscillator tube 1 and the grid electrode 19 of the power amplifier or frequency multiplier tube 17. This circuit includes a source of direct current 37 having its negative terminal con- ;nected through choke coil 40 with grid electrode 19, and having its positive terminal connected through chokecoil 39 with plate electrode 4. A signaling key 41 may be interposed in series with this circuit and may be used in lieu of the key 33 for the trans The supply of high potential to the output circuit of tube 1 is completed by a connection from. the negative side of the source 37 throughchoke coil 38 with the mid-tap connection 8 of secondary winding 7 of filament transformer 5.

By this circuit arrangement hi h potential is supplied to the output circuit of tube 1 simultaneously with the biasing the grid electrode of the tube 17 with a correspondingly high'potential. Where it may be desirable to vary the negative C voltage from the source a resistance potentiometer may be placed across the terminals of the machine and an adjustable tap taken from the resistance potentiometer to the grid electrode 19 through cholre coil 4h instead of direct to the negative terminal of the chine 37.

The circuit arrangement illust proven to be particularly ad much it is seldom the eas es crystal controlled master oscillator is able to use a voltage of a higher order than that which is necessary for the operation of the frequency multiplier and amplifier. The second and third harmonics of the master oscillator may be brought out in the power amplifier tube by virtue of the circuit arrangement of the present invention. Other harmonics are often present but are not as useful in the frequency multiplier system as are the second and third harmonics. It is importantthat high insulation be provided in the filament transformer for the protection of the system against breakdown.

While I have described my invention in its preferred embodiment, I desire that it be understood that modifications may be made and that no limitations upon the invention are intended other. than are imposed by the scope of the appended claims.

What I claimas new and desire to secure by LettersPatent of the United States is as follows:

1. In a signal-transmission system an electron tube oscillator, an electron tube amplification system having its input circuit con nected to the output circuit of said oscillator and a high potential source for impressing a positive potential u on the output circuit of said oscillator an a negative potential Epon the input circuit of said power ampli- 2. In a signal transmission system a plurality of electron tubes each having grid, filament and plate electrodes, input and output circuits interconnecting said electrodes, one of said electron tubes being arranged for the production of high frequency oscillations, another of said electron tubes being arranged for the amplification of the oscillations thus produced and a high potetial source interposed between the output circuit of said first mentioned electron tube and the input circuitof said second mentioned electron tube for impressing a positive potential upon the plate electrode of said oscillator and impressing negative potential upon the grid electrode of said power amplifier.

3. In a signal transmission system a plurality of electron tubes each having grid, filament and plate electrodes, input and output circuits interconnecting said electrodes, one of said electron tubes functioning for the production of high frequency oscillations and the other of said electron tubes functioning as a power amplifier, a piezo' electric cri stal connected in the input circuit of said rst mentioned electron tube for sustaining oscillations in said circuits at a frequency corresponding to the frequency of said piezo electric crystal element, and

a value repiezo electric potential having its sitive terminal connected with the plate e ectrode of said first mentioned tube and having its negative terminal connected with the grid electrode of said second mentioned tube.

4. In a high frequency'signal transmission system a combination of a lurality of electron-tubes, each of said tn 5 having grid, filament and plate electrodes, input and output circuits interconnecting said electrodes, at leastone of said tubes functioning as an oscillator and another of said tubes functioning as a power amplifier, means coupling the output ofsaid oscillator with the input of said power amplifier and a circuit interposed between the plate electrode of said oscillator and .the grid electrode of said power amplifier, said, circuit including a source of potential with choke coils on' opposite sides thereof, the negative terminal of as an oscillator oscillations and another 'of said electron said source connecting with the grid elective terminal of said source connecting with the plate electrode of said oscillator.

5. In asignal transmission system a plurality of electron tubes each having grid, filament and plate electrodes, input and out ut circuits interconnecting said electro es, one of said electron tubes operating to generate high. frequency tubes operating as a power amplifier, means coupling the output circuit of said oscillator with the input circuit of said power amplifier, a circuit including a source of direct current, said circuit being connected in inverse order to both the output circuit of said oscillator and the input circuit of said power amplifier ALBERT H. TAYLOR. 

